Revision is an essential part of the preparation process for any subject, including Electrical Engineering as an optional subject for the UPSC exam. Here, we will discuss the best revision strategy for this subject, keeping in mind the guidelines provided.

1. Understand the Syllabus:
- Familiarize yourself with the syllabus of the Electrical Engineering optional subject. Understand the topics and subtopics that need to be covered.

2. Create a Study Plan:
- Develop a study plan that allocates time for each topic based on the weightage and your understanding of the subject.
- Break down the syllabus into manageable parts and set realistic goals for each study session.

3. Recapitulate the Basics:
- Start your revision by revisiting the fundamental concepts of Electrical Engineering. Review basic theories, laws, formulas, and definitions.
- Understand the underlying principles, as they will serve as a foundation for solving complex problems.

4. Review Previous Notes and Materials:
- Go through your class notes, textbooks, and reference materials. Identify important points and concepts that need reinforcement.
- Highlight or make notes of key information for quick reference during revision.

5. Practice with Previous Year Question Papers:
- Solve previous year question papers to familiarize yourself with the exam pattern and the types of questions asked.
- Analyze your performance and identify areas where you need improvement. Focus more on these topics during your revision.

6. Utilize Online Resources:
- Online platforms like EduRev provide a wide range of study materials, practice questions, and interactive quizzes.
- Take advantage of these resources to enhance your understanding of complex topics and test your knowledge.

7. Seek Clarification:
- If you encounter any doubts or difficulties while revising, don't hesitate to seek help from your professors, fellow students, or online forums.
- Clearing your doubts will ensure a better understanding of the subject.

8. Create Visual Aids:
- Use diagrams, flowcharts, and concept maps to visually represent complex theories and formulas. Visual aids can help in better understanding and memorization.

9. Practice Time Management:
- During revision, practice solving problems within a specified time frame to improve your speed and accuracy.
- This will also help you manage time effectively during the actual exam.

10. Regular Revision:
- Plan regular revision sessions to reinforce your learning. Regular revision will help you retain information for a longer period.

In conclusion, the best revision strategy for Electrical Engineering as an optional subject for the UPSC exam involves understanding the syllabus, creating a study plan, reviewing previous notes and materials, practicing with question papers, utilizing online resources, seeking clarification when needed, creating visual aids, practicing time management, and engaging in regular revision. By following these strategies, you can enhance your understanding, retention, and problem-solving skills in Electrical Engineering.